Optics: measuring and testing – By polarized light examination – With light attenuation
Patent
1993-11-16
1995-05-02
Pham, Hoa Q.
Optics: measuring and testing
By polarized light examination
With light attenuation
356387, 250561, G01B 1114, G01N 2186
Patent
active
054124760
ABSTRACT:
Longitudinal position of the end of a drill bit (21) is determined in order to accurately control depth of a hole to be drilled. A drill bit (21) is rotated at a predetermined speed and caused to penetrate a light beam of known vertical position. The light beam, which is generated by a light emitting diode (50) and received by a photo transistor (54), is modulated by the flutes at the tip of the rotating bit to cause the photo transistor to provide an output signal that is modulated at a frequency that is a fixed multiple of the speed of the rotating bit. An operational amplifier (74) having a feedback circuit (80) that is resonant at the frequency of the modulated electrical signal from the photo transistor receives the photo transistor output signal as its input. The amplifier output experiences a sharp increase in magnitude upon receipt of the input signal at the resonant frequency of its feedback circuit. Thus a reference position of the bit is signalled and stored by the bit spindle control (18) that will move the bit longitudinally to a depth determined on the basis of the known bit reference position.
REFERENCES:
patent: 4340326 (1982-07-01), Buonauro et al.
patent: 4436427 (1984-03-01), Schwartz
patent: 4502823 (1985-03-01), Wronski et al.
patent: 4745557 (1988-05-01), Pekar et al.
patent: 5004930 (1991-04-01), Gremaud et al.
patent: 5005978 (1991-04-01), Skunes et al.
patent: 5026165 (1991-06-01), Faville
patent: 5212391 (1993-05-01), Wachli
patent: 5293048 (1994-03-01), Skunes et al.
Optima Industries, Inc.
Pham Hoa Q.
LandOfFree
Drill bit position sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Drill bit position sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Drill bit position sensor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1141615